Katerina Alexandre Hartford Graham (born September 5, 1989) is a Swiss-born American actress, model, singer and dancer. She is known for her role as Bonnie Bennett on The CW supernatural drama The Vampire Diaries (2009–2017).

Her film credits include The Parent Trap (1998), 17 Again (2009), The Roommate (2011), Honey 2 (2011), Addicted (2014), and All Eyez on Me (2017). In music, she was previously signed to A&M/Octone and Interscope Records, and has released two extended plays and two studio albums.